The National Labor Relations Board has set April 21 for a hearing on the United Auto Workers request for a revote on unionizing Volkswagen's Chattanooga plant, but it isn't known if any politicians cited in the case will be asked to testify.

NLRB spokesman Gregory King said Friday that while the hearing date is fixed, the time and the location weren't scheduled yet. He said the federal agency hoped to have more details Monday.

Hamilton County officials have talked with the NLRB about reserving the courthouse's commission room, said spokesman Mike Dunn. He said the room would be reserved Monday through Friday.

Anthony Riedel, a spokesman for the National Right to Work Foundation, said the Virginia-based anti-UAW group doesn't have a preference for what city in which to hold the hearing.

"We're ready to present evidence on how the will of the employees should stand," he said.

The UAW did not return emails seeking comment on the hearing.

The NLRB said it will offer parties the chance to give testimony and to examine and cross-examine witnesses. Riedel said the parties in the case will inform the NLRB who they wish to subpoena for the hearing.

The union, in its appeal of last month's vote in which workers rejected the UAW organizing effort 712 to 626, cited interference in the election by political figures in Tennessee.

It said that Gov. Bill Haslam; state House Speaker Beth Harwell; House Majority Leader Gerald McCormick, R-Chattanooga; Senate Speaker Pro Tem Bo Watson, R-Chattanooga; and others conducted a coordinated and coercive campaign to deprive workers of an election free of intimidation, threats and interference.

"The state officials' campaign included, without limitation, publicly announced and widely disseminated threats...that state-financed tax and other incentives and financial benefits" would be withheld from Volks-wagen if the union was recognized, the UAW said.

The union also alleged that U.S. Sen. Bob Corker, R-Tenn., escalated the threats when he said that he'd been assured by VW that if the workers voted against the UAW, they would be rewarded with a new product line at Chattanooga.

Corker on Thursday said in Chattanooga that he's a person who speaks to issues, and if something happens that he thinks will negatively affect the city, he's going to voice his opinion.

"I'm glad that I did. I'm glad the workers made the decision that they did," he said. Corker said the UAW was causing a problem regarding economic development recruitment and would in the future.

He also has said the UAW is trying to muzzle public officials from weighing in on issues.